Most Helpful Guy
While all of this may sound QUITE incriminating... It is also quite plausible that he is Not having an affair and all of this happens to be circumstance. If I may ask, how long have you 2 been together/married; and how old is your child? I think it is Always a good idea in this day and age to be attentive to what our significant other is doing - as; even those with faithful intentions are sometimes led astray... BUT that does not mean it is actually happening here. You have an idea that he may be, and you have noticed things that as stated may appear to support your suspicion. I would suggest that you not let him know you are suspicious - and pay more attention to his actions than you ever have before. If you have friends willing to help in this watch, enlist them. Hopefully - it will turn out to be nothing, and you will be glad the 2 of you did not wind up having the "jealous controlling ! itch" fight. If on the other hand - you do actually come across proof (which is gonna hurt like hell) - then at least you will know, and when you confront him there won't be any question or doubt of guilt.
Most Helpful Girl
Read up on the signs of cheating, and you'll see that changes in behaviour, and changes on how he treats you are two concerning factors. If nothing else, they are concerning factors just because they are changes for the worst. He is your husband and should be putting you and your child first. Not to say he shouldn't have friends and attend events, but the behaviour he is showing is sort of frat-boy type of behaviour and that's just not good enough to me when I think of what a man, married, and made a commitment to his wife and family is all about. I can understand going out and having fun, but not at the expense of his wife and child's feelings, especially big occasions like your US 4th of July.
Also, it's a bit of a disrespectful move to continue giving attention to a guy who is rude to you. It's one thing if you don't get on together, fine - then don't speak, but if he's openly saying things to you and your husband does nothing about it, I have to wonder why.
Only you know for sure what he's like, and if you find things out further it may or may not be cheating, but so far, this behaviour is showing red flags that his respect for you is dwindling and after that, many marriages suffer unless this is fixed fast.